1. Field
The invention is related to a pressure housing assembly, and more particularly to pressure housing assembly suitable for use in underwater environments.
2. Related Art
One of the key challenges in subsea system design is to provide a one atmosphere hollow pressure vessel attached to transmission cables that can be used to house components needed in various subsea industries such as communications, defense and offshore oil and gas markets with the ability to withstand the hydrostatic pressures of deep and ultra-deep sea environments. Designing this type of pressure vessel to be hermetically sealed and resistant to corrosion while making the pressure housing capable of being re-entered if necessary has proven to be a significant design challenge. In communications and control systems, it is common practice to package or splice copper and/or fiber optic conductors in pressure vessels that are connected to a cable. One significant challenge has been to maintain the structural integrity of the pressure vessel housing while keeping the overall weight as light as possible for assembly and deployment purposes. Many methods have been employed to solve these technical problems. These methods typically require separate mechanical parts or sub-assemblies that are bolted or welded together to form the complete pressure vessel assembly. This welded method does not allow re-entry into the pressure vessel if needed during the manufacturing, testing and handling prior to deployment. The bolted case and cover method requires a significant number of high strength fasteners and extra material around the fasteners to transfer the load into the housing components resulting in thick walled housings.
Some of the conventional technology/methodology includes:                1. All metal pressure housing with one or more bolted on end caps;        2. Pressure housings with end caps that are attached via internal screw threads;        3. Pressure housings with external slide shell configuration requiring internal axial load end-cap support structure;        4. All metal pressure housing vessel with welded case and cover type construction;        5. Two piece all metal “clam-shell” type construction;        6. Non-metallic pressure vessel housing; and        7. Hybrid pressure vessel construction using metallic and non-metallic construction components.        
Re-entry into the enclosure is needed if a problem is encountered during any of the critical assembly phases or if other problems arise that cannot be fixed externally. The current invention provides a logical means to provide a one atmosphere, hermetically sealed pressure vessel that can withstand the effects of high hydrostatic pressure and allow for re-entry into the pressure vessel at any time to access the contents of the pressure vessel while not compromising any part of the pressure vessel during disassembly and reassembly.